Caused directly by animal droppings not picked up by a dog or cat’s owner.
10,000 cases annually in the United States alone. Small children are the most susceptible to this disease.
Symptoms
include fever, cough or wheezing, enlarged liver, rash, or swollen lymph nodes.
When the larvae in the intestine make their way through the bloodstream to the
eye, it is known as ocular toxocariasis, or ocular larva migrans, which may
lead to a permanent loss of vision.
Pathophysiology:
Human infection with Toxocara, the parasitic larvae of canine or feline
roundworms, is known as visceral larval migrans (VLM) systemically and ocular
larva migrans (OLM) when it affects the eye. Two nematode larvae can cause
toxocariasis. Both are round worms found in the intestines of dogs (T. canis)
and cats (T. cati). About 20% of dogs release Toxocara canis in their stool.
Patients can become infected after accidentally swallowing infective Toxocara
eggs from larvae in soil or other contaminated surfaces. Puppies usually
contract Toxocara canis from the mother before birth or from her milk. The
larvae mature rapidly in the puppy's intestines and when the pup is three or
four weeks old, they begin to produce large numbers of eggs that contaminate
the environment through the animal's stool. The eggs soon develop into
infective larvae. Contraction occurs from ingesting contaminated soil or feces.
Once
ingested, the eggs hatch and larvae penetrate the intestinal wall and are then
carried by the circulation to various tissues--liver, heart, lungs, brain,
muscle, eyes--via blood and lymph. Ingested eggs may remain viable for years.
While the larvae do not develop further in these sites, they can cause severe
local inflammatory reactions.
With
the ocular form, one or more larvae become trapped in the eye, causing a
granuloma in the retina. The nematode may reside beneath or within the retina,
or it may extend into the choroid or vitreous. It may remain viable for several
years in the eye. The nematode may enter the eye via the central retinal
artery, and will likely manifest as a peripheral granuloma. If the nematode
enters via the short posterior ciliary arteries, the granuloma will likely be
at the disc, macula or elsewhere in the posterior pole.
Other Diseases that can be passed from pet waste to
humans:
Campylobacteriosis - a bacterial infection carried by dogs and cats that frequently causes diarrhea in humans.
Salmonellosis - the most common bacterial infection
transmitted to humans by other animals. Symptoms include fever, muscle aches,
headache, vomiting and diarrhea.
Toxoplasmosis - a parasite carried by cats that can cause birth defects if a woman becomes infected during pregnancy. Can also be a problem for people with depressed immune systems.
Other problems caused by pet droppings:
Dog and cat waste left on the ground can be washed
into storm sewers, most of which drain directly into natural water bodies.
There the waste contributes to all sorts of problems - from sick kids to mucky
algae that suffocates fish and is sometimes poisonous to humans
The same bacteria that make pet waste dangerous to
people in parks can make water unsafe for swimming or drinking. Children and
others can get sick if they dunk their heads or accidentally get a mouthful of
polluted water. And when waste gets into shellfish beds, it can make clams and
oysters unsafe to eat.
Factors affecting stormwater pollution:
not picking up dog droppings: left dog droppings
will be carried into the stormwater system next time it rains. (Imagine the
cumulative effect of all the dogs in your neighbourhood.)
It
is the responsibility of an animal’s owner to remove the droppings from areas
where another human might come in contact with them. Bare-footed children and
children who fall into a pile of animal
feces face a serious threat of illness and even blindness from exposure to the
parasites that live in the intestines of domestic animals. The Pinellas Trail
is particularly violated by pet owner’s whose ignorance or disregard for others
is evident by the multitude of droppings that can be seen along the length of
the park. If you witness a pet owner allowing the droppings to remain let them
know the dangers and their responsibility as a pet owner to remove the waste.
If you have children educate them of the danger and avoid pet droppings at all
costs. If you know a pet owner that regularly allows and does not clean up pet
droppings report them to the Pinellas Animal Services Department 12450 Ulmerton Road
Largo 33774 (727) 582-2600
TDD (727) 582-2636